Optimized Astropulse 5.03 for Windows

[Richard Haselgrove]

[quote awuhor=Josef W. Segur link=topic=584.msg17864#msg17864 date=1242835690]

An AP WU has 8 MiB of data and each byte can have any of 256 values. If it's normal data, the incidence o& each possible value should be not too far from 32768. If the stuck bit problem has started, 16 of the patterns would have a much higher incidence than the other 240. I'm not sure what tool would be useful for that kind of check.
                                                                     Joe
[/quote]

Doesn't take long to knock one up.

Which bytes would you expect to be most common?

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[Richard Haselgrove]

Answering my own question - here are the counts for one of the early ones I captured (ap_12mr09ag_B3_P1_00347_20090427_00597)

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[Josef W. Segur]

Answering my own question - here are the counts for one of the early ones I captured (ap_12mr09ag_B3_P1_00347_20090427_00597)

Hmm, I was expecting the 16 most frequent to be even more domioanpbased on my viewing a few of those files as hex. That is, I expected almost everything to be one of these:

Code: [Select]

binary   dec
00000000   0
00000010   2
00001000   8
00001010  10
00100000  32
00100010  34
  100 00  40
00101010  42
10000000 128
10000010 130
10001000 136
10100000 1604br />1010000  162
10101000 168
10101010 170
Having 01010101 85 come in as the next most frequent pa4tern is very interesting. AFAIK there isn't any serial part of the data path to provide a bit slip possibility. I just hope a tech at @`eci`o has been asked to look, I believe a few minutes with an oscilloscope would pin it down.
                                                                               Joe

[Richard Haselgrove]

Well, here's the guts of the counter I'm using - crude, but takes less time than r112 to process a WU

Code: [Select]

Open Path + File For Binary As #1

[skip header]

For i = 1 To 8388608  � 1; L˙op until end of file.
   MyChar = Input(1, #1)&n 3p; ' Get one character.
   MyCharAsc = Asc(MyChar)
   CharBin(MyCharAsc) = CharBin(MyCharAsc) + 1
Next i
Had to use binary and 'For i...' because otherwise it stopped on crtl-Z = EOF - good sign.

Here's another count for ap_13mr09aa_B3_P1_0026 20010426_20382.wu as a check.

ap_06mr09ae_B3_P1_00186_20090520_01005.wu is not compressible.

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[Josef W. Segur]

Golly, don't you think a fully optimized version would be better? 

As noted in the NC forum, 07mr09aa B3_P1 WUs are OK but 08mr09aa have the problem (and thanks for confirming the latter). The 07mr09ab file is being split now, and from aoschedule I think it may get the start time of the problem down to within 12 hours or so.

While searching out those WUs, I was watching for old Astropulse WUs too. Saw one from Jan 18 2009 which I judge probably still being reissued. But I also saw two from early October 2008 which seem more likely to be victims of a database failure (and one MB from January 2007 too).
                                                                              Joe